Sydney Memory and Ageing Study (MAS)

The Sydney Memory and Ageing Study (MAS) is a longitudinal cohort run by the Centre for Healthy Brain Ageing (CHeBA) at UNSW Sydney. It started in 2005 to measure how often mild cognitive impairment and dementia arise in older Australians and what predicts cognitive decline. Participants were assessed every two years over 14 years with cognitive, medical, blood, genetic and imaging measures. Researchers apply for the data through Dementias Platform Australia (DPAU).

Composition

At baseline the cohort held 1,037 community-dwelling adults without dementia, aged 70 to 90, drawn at random from the electoral roll in two areas of Eastern Sydney. About a third met criteria for mild cognitive impairment at baseline. Structural MRI was done in 554 participants at baseline, and subgroups also had functional MRI. A later analysis used MRI from 605 participants with scans at baseline, 2-year or 6-year follow-up. DPAU lists MRI-derived measures (white matter hyperintensities, cortical and subcortical volumes, diffusion indices, microbleeds) and raw MRI as data that can be requested.

Acquisition

Baseline MRI was acquired on two Philips 3 T scanners (Intera Quasar and Achieva Quasar Dual) with matched T1w (1 mm isotropic) and FLAIR protocols; follow-up scans used the Achieva Quasar Dual. The SWI sequence used for microbleed work on that scanner has TR 25.33 ms, TE 40.33 ms and 1.1 mm slices.

Annotations

Hassanzadeh et al. (2025) had two radiologists independently mark cerebral microbleeds on 30 MAS SWI scans, finding 60 microbleeds. DPAU lists a microbleed data category for MAS; whether it includes these labels is not stated.

Known limitations

• The number of participants with MRI or SWI at each wave is not published as a single table.
• Raw MRI is provided only after consultation with the CHeBA imaging team; DPAU's analysis environment is meant for tabular data, and data cannot be downloaded from it.
• Access costs an application fee and is limited to an approved project.
• The 2025 paper calls the SWI subset confidential, so the microbleed labels may not be available.